During manufacture of a semiconductor device, interconnect layers are often created using aluminum or other conductive elements and compounds. Following formation of an interconnect, a spin-on-glass (SOG) plasma etch back step is performed to planarize the exposed semiconductor surface, including the exposed aluminum interconnect and an anti-reflective coating (ARC). A titanium compound forms in globs, or bumps on the semiconductor wafer during SOG etch back when the ARC film is exposed to the plasma. The bumps remain on the wafer, and are easily seen in high concentrations at 40.times., all over the wafer. The bumps can be 1000 Angstroms or greater in both height and width. As a result, the semiconductor product must be scrapped.
Past attempts at cleaning or otherwise removing titanium containing bumps on semiconductor leads have resulted in peeling of the fully manufactured semiconductor. Some attempts have resulted in faulty semiconductors, i.e. having poison vias.
It is therefore an object of the present invention to safely manufacture semiconductors having interconnect leads and anti-reflective coating. It is another object of the invention to perform an etching process on such a semiconductor without permanent formation of titanium-containing clusters or bumps, especially on the interconnect leads. It is yet another object of the present invention to manufacture such a semiconductor without detrimental effects to the final product such as peeling and poison vias.